What do u mean by refractory?
1 : resisting control or authority : stubborn, unmanageable. 2a : resistant to treatment or cure a refractory lesion. b : unresponsive to stimulus. c : immune, insusceptible after recovery they were refractory to infection.
What is a refractory in construction?
Refractory materials are those that can withstand high temperatures without the heat damaging their structure, resistance, or thermal conductivity. In the case of bricks, the chemical composition of refractories is different from that of regular bricks, which also influences their color and thermal conductivity.
What is refractory pain?
Intractable pain or refractory pain occurs when pain cannot be adequately controlled despite aggressive measures.
What does a refractory engineer do?
Common job titles include refractory technician, refractory worker, and refractory bricklayer. A refractory technician designs high-temperature equipment and heating structures using heat-resistant elements such as minerals, ceramic, and brick components.
What is fire refractory brick?
A fire brick is a block of refractory ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces. A refractory brick is designed mainly to withstand high heat, but should also usually have a low thermal conductivity to save energy.
What is an example of refractory?
The definition of refractory is stubborn or hard to manage, or heat resistant. An example of someone who is refractory is a person who refuses to listen to the rules. An example of something refractory is a material like silica or alumina that are difficult to melt.
How are refractory metals made?
Refractory metals, heavy alloys, and hardmetals are typically fabricated by powder processing methods. Their main constituents are extracted from ores as powders and their high melting temperatures prevent processing by conventional melt-based forming technologies.
What is a example of refractory?
Examples of conducting refractories are silicon carbide (SiC) and zirconium carbide (ZrC), whereas examples of nonconducting refractories are silica and alumina. Insulating refractories include calcium silicate materials, kaolin, and zirconia.
Which of the following is an example of natural refractory?
Explanation: Chromite, along with graphite, is a common neutral refractory material. Chromite has an approximate fusion temperature of 2180oC while that of graphite is 3000oC. Dolomite and magnesia are basic refractories, whereas silica is an acid refractory. 7.
What are refractory symptoms at end of life?
Pain, dyspnea, persistent emesis, and agitated delirium are the symptoms most commonly requiring sedation (Rousseau 1999, Braun 2000).
What are the requirements of a good refractory?
A good refractory should have high RUL value. It is defined as the ratio of its pore volume to the bulk volume. Porosity is an important property of refractory bricks, because it affect many other characteristics like chemical stability, strength, abrasion- resistance and thermal conductivity.
Why do we use refractory bricks?
A fire brick, firebrick, or refractory is a block of ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces. A refractory brick is built primarily to withstand high temperature, but will also usually have a low thermal conductivity for greater energy efficiency.
How do you use refractory in a sentence?
How to use Refractory in a sentence
- The Convention took measures against the emigres and the refractory priests.
- The materials used in the construction of furnaces are divisible into two classes, namely, ordinary and refractory or fire-resisting.
Which metal is known as refractory?
Refractory metals are a group of metallic elements that are highly resistant to heat and wear. It is generally accepted that tungsten, molybdenum, niobium, tantalum and rhenium best fit most definitions of refractory metals.
What is refractory?
refractories, bricks of various shapes used in lining furnaces. 1 obstinate, perverse, mulish, headstrong, intractable, disobedient, recalcitrant, ungovernable. 1 obedient, tractable.
What is the difference between headstrong and refractory?
While all these words mean “not submissive to government or control,” refractory stresses resistance to attempts to manage or to mold. When can headstrong be used instead of refractory?
What is the origin of the word Refractarius?
Refractarius, like refractory, is the result of a slight variation in spelling. It stems from the Latin verb refragari, meaning “to oppose.”